Air pump



Sept. 28, 1954 H, 1 RAND 2,690,295

AIR PUMP Filed Feb. 25, 1951 INVENTOR. Hav/er c7.' /-A No Patented Sept. 28, 1954 AIRPUMP Henry J. Rand, Bratenahl, Ohio, assignor to Air Mass, Inc., Bratenahl, Ohio, a corporation of Ohio Application February 23, 1951, Serial No. 212,398

3 Claims.

This invention relates to an improvement in air pumps and more particularly to diaphragm operated pumps.

One of the objects of the present invention is to provide a novel attaching means for a diaphragm to a pump chamber Wall.

Another object of the present invention is to provide a novel attachment between a reciprocating drive means and a diaphragm.

Another object of the present invention is to provide a novel attaching means for a diaphragm to a pump chamber wall and a novel attachment between a reciprocating drive means and the diaphragm.

Another object is to make a diaphragm for a pump of the type described and its associated elements all in one integral piece. This construction is cheaper, easier to make and easier to assemble and replace.

Other features of my invention reside in the arrangement and design of the parts for carrying out their appropriate functions.

Other objects and advantages of my invention Will be app-arent from the accompanying drawings and description and the essential features thereof Will be set forth in the appended claims.

In the drawings, Fig. l is a side elevational view of the motor driven pump of this invention;

Fig. 2 is a vertical sectional view taken along the line 2-2 of Fig. 1. The diaphragm is shown in its expanded position by the solid lines and in its collapsed position by a dot-dash line; While Fig. 3 is a sectional view of the diaphragm per se in its unstressed condition and with the reciprocating driving means shown in dot-dash lines.

The drawing discloses a motor driven pump, shown broadly by reference numeral II, the motor being designated broadly by I2.

Pump II consists of a base I3, a housing I4 and a cap I5. These elements are rigidly connected together by screws I6. The pump Il is attached to motor I2 by ange Il, which is attached to the motor nange by removable fastening elements I8. The motor I2 is also supported by screw I9 extending from base I3 to give a firm support to the motor. Flange I1, rigidly attached to the motor ange, assures a correct alignment for the diaphragm reciprocating means, to be later described.

The base I3 contains an intake and exhaust valve. An intake valve aperture is shown at and an exhaust valve aperture at 2da in base I3. The air is brought in under base I3 and pumped into pressure line 2i. An air operated intake valve 22 and an air operated exhaust valve 22a are mounted in the apertures in the base. 'Ihese valves may be small leaves of rubber. Restricted apertures 23 and 23a are blocked by valves 22 and 22a when in their closed position. Strainers 24 and 24a, to prevent the admission of foreign matter to the pump, are also located in the respective valve apertures. These strainers are force fit into their respective openings to hold the valves in place for slight vertical movement. A closure plug 25 blocks the passage between the intake chamber and the pressure line 2|.

A readily expandable and contractble chamber for pumping the fluid is shown at 26. This expansion chamber is formed by an upstanding annular wall 2l, integral with base I3, and the diaphragm 28. Wall 21 has a concave outer surface to detachably mount the flexible diaphragm.

The invention in this application relates to this novel diaphragm 28 and its operating connections. It may be made of rubber, plastic, or any other iexible material which will have a long life during many repeated oscillations. Flexible diaphragm 2B, in its unstressed condition, as shown in Fig. 3, consists of a fiat circular disc 29 With an integral, annular and peripheral flange 30 extending at approximately right angles from its under face and a ring shaped member 33 eX- tending from its upper face. Flange 30, disc 29 and ring 33 may be molded as a one-piece, integral unit, or they could be fabricated separately and then permanently attached together. The disc 29 and ange 3U may also be made in one piece and later attached to ring 33. A bead 3l extends around the lower, outer edge of flange 30. This flange is mounted to embrace the outside face of wall 2l, as shown in Fig. 2, and then a snap ring 32 is placed radially outside of the assembly to lock the diaphragm in position.

A means to reciprocate the diaphragm to pump the uid is also provided. The integral projection or ring-shaped member 33 extends from the upper surface of disc 29 of flexible diaphragm 28. This projection 33 has a bore or aperture 34 with an axis extending perpendicular to the axis of disc 29. Recess 35, in projection or ringshaped member 33, supports an eccentric driven member 36.

In the present embodiment, motor I2 eccentrically drives shaft 31 by means of motor shaft 38. The eccentrically driven member or bearing 36 is mounted on eccentrically driven shaft 31. The inside race of bearing 36 is a force fit on shaft 3l. The outside race nts snugly in recess 35.

An alternative construction to reciprocate the pump might be a cam driven by motor shaft 38 and mounted in recess 35.

In the operation of the pump, motor shaft 3B rotates and reciprocates bearing 36 by eccentrically driven shaft31. This reciprocating means drives diaphragm 28 through ring 33 to expand and contract the expansion chamber 26 of the pump, as shown in. full and dot-dash lines in Fig. 2. Thev ud nows through intake valve 22 through the expansion chamber 26 and out exhaust valve 22a into pressure line 2 I. v

A practical application of this pump is shown. in my copending application Serial Number 201,085, filed December 16, 1950,` land entitled'y Hollow Mattress and Inflation Control There-v for. In this application the pump is used for compressing air but it could very readily be used for compressing or pumping other fluids.

The diaphragm, the subject of this invention may very Well be used for other applications and in other types of pumps.

What I claim is:

1. A pump diaphragmv consisting of a substantially flat circular exible disc, an integral depending peripheral annular ange projecting from one face thereof adapted to be mounted over an upstanding circular wall surrounding an expansion chamber of a pump, a bead on the outer lower edge of said flange, an integral ring-shaped projection extending from the middle of the other face of said disc, the axis of said ring extending perpendicular to the axis of said disc, and said .ring having its inner periphery provided with an annular recess, whereby to retain an eccentrically driven member to reciprocate said diaphragm to alternately expand and contract said chamber, and whereby a retaining member surrounding said ange and wall may be held in place by said bead.

2. In a pump comprising a base having an upstanding annular Wall, there being fluid inlet and outlet openings through said base within said annular wall and valves cooperating with said openings to open and close the same for pumping ing annular ange, said flange telescopically receiving said upstanding wall, a bead on the lower edge of said annular flange, means securing said flange to said annular wall, an integral ringshaped projection extending upwardly from the center of said diaphragm with the axis of said ring perpendicular to the axis 'of said annular flange, an eccentric snugly engaged in said ringshaped projection, means for rotating said eccentric, an outermost surface on said annular Wall concave outwardly, said flange securing means comprising a snapring outside said flange and releasably holding said flange in snug engagement with said outermost surface of said wall, said ring-shaped projection containing a groove in its inner periphery.

3. In a pump comprising a base having an upstanding annular Wall, there being fluid inlet and outlet openings through said base within said annular Wall and valves cooperating with said openings to open and close the same for pumping action; the combination therewith of a flexible rubberlike diaphragm having an integral downwardly extending annular ange, means securing said flange to said annular wall, an integral ring-shaped rubberlike projection extending upwardly from the center of said rubberlike diaphragm with the axis of said ring perpendicular to the axis of said annular flange, said projection having its inner periphery provided with an annular recess, an annular bearing in said recess and retained by the rubberlike characteristic of said projection, and a driving member engaged inside said bearing for oscillating said diaphragm.

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 1,976,098 Smith Oct. 9, 1934 2,148,957 Morris Feb. 28, 1939 2,240,371 Linch et al Apr. 29, 1941 2,575,398 Schroeder Nov. 20, 1951 FOREIGN PATENTS Number Country Date 346,756 France Dec. 9, 1904 

